Structure and properties of fluoride phosphate glasses

The structural model of fluoride phosphate glasses can be described as Al(F,O)6-octahedral chains bonding by mono- and diphosphate groups and cations. Proofs are given of Raman and NMR spectroscopy. These glasses posses special optical properties making them attractive candidates for application in high performance optics. UV transmittance, solarization, and luminescence properties were investigated. Glasses melted under reducing conditions show high UV transmittance, only small solarization effects after irradiation at 248 nm, but high effects at 193 nm. Glasses doped with 75 ppm Ce yield higher solarization effects than glasses without cerium ions. After irradiation the Ce3+ luminescence has nearly vanished.